Sound damping arrangement

ABSTRACT

A tubular element conveys fluid through a passage having an enlarged passage portion. Accommodated in the passage portion axially spaced from one another is a pair of plates each provided in the respective outer margin with a concentric annulus of apertures. An insert is accommodated between the plates and defines with the wall of the element an annular clearance. Its respective end faces face the plates and are each provided with recesses communicating with the clearance and with one of the apertures. A plurality of depressions are provided in the upstream one of the endfaces and register with respective apertures and a plurality of closing members are each received in one of the depressions closing the same except for a reduced cross-sectional area. Biasing means yieldably biases the respective closing member into closing position in which it resiliently closes partially the respectively associated aperture.

United States Patent [72] Inventor Werner Mrosek 2,864,403 12/1958 Deilyet a1 181/65 X Rheydterstrasse 134, 404 Neuss, Germany 2,919,719 1/1960Boulet... 138/43 [21] Appl. No. 90,915 3,074,437 1/1963 Mercier 138/31Flled 1970 Primary Examiner-Robert S. Ward, Jr. [45] Patented 1971Altorne\'Michael S. Striker [32] Priority Feb. 19,1970 [33] Germany 1P20 07 527-8 ABSTRACT: A tubular element conveys fluid through a passagehaving an enlarged passage portion. Accommodated in the assa e ortionaxiall s aced from one another is a [54] SOUNP AR RANGEMENT pair ofplate s e ch provided in the respective outer margin 11 clalms'anrawmgwith a concentric annulus of apertures. An insert is accom- [52] U.S.Cl181/47 A, modated between the p tes and defines wit the all of the I181/36, 181/65, 138/3 ]38/43 element an annular clearance. ltsrespective end faces face the [51] lnt.Cl F161 55/04, plates and areeach provided i h recesses mm i ing 7 F01 1/20 with the clearance andwith one of the apertures. A plurality [50] Field of Search 181/47, 57,of depressions a e p o i ed n e up t eam o e of the end- 47.|, 64.2, 65,35, 36.2, 36 4], 49, 36,4; 138/26 faces and register with respectiveapertures and a plurality of 30 31 42 43 closing members are eachreceived in one of the depressions closing the same except for a reducedcross-sectional area. References Cited Biasing means yieldably biasesthe respective closing member UNITED STATES PATENTS into closingposition in which it resiliently closes partially the 2,674,096 4/1954Marshall 138/43 x respectively asmifled aPerme- 2.838,072 6/1958 Stumm181/47 A PAIENTEUmJv 30 Ian saw 1 or 2 vL-a L E n R K mu N mm aPATENTEDNEW 30 |9Tl SHEET 2 [IF 2 INVENTOR Una/m 11min 1 SOUND DAMPINGARRANGEMENT BACKGROUND OF THE INVENTION The present invention relatesgenerally to damping arrange ments, and more particularly to a sounddamping arrangeof course, the assembly of such an arrangement isdifficult and complicated effectiveness of this ar- SUMMARY OF THEINVENTION It is, accordingly, an object of the present invention toovercome the aforementioned disadvantages of the art.

It is advantageous but not necessary that each of the apertures isassociated with one of the depressions and with one of the closingmembers.

An arrangement constructed according to my invention as through nearlyI". which occur in the nulii of apertures in the first-mentioned plates.

The closure members may be configurated as plugs of small parativelysmall or low pressure.

The novel features which are considered as characteristic for theinvention are set forth in understood from the following description ofspecific embodiments when read in connection with the accompanyingdrawing.

FIG. 3 is a view similar to FIG. 1 but illustrating still anotherembodiment of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Discussing now the drawing indetail, and firstly the embodiv A, however, the members As FIG. 1 shows,there are accommodated in the passage portion Ia two plates 6 and 9located at its opposite axial ends.

annulus 8 preferably corresponds at least substantially to thecross-sectional area of the passage portion 3. The same is true withrespect to the passage portion of the combined crosssectional area ofthe apertures of the annulus 10. The plates 6 and 9 may be of one piecewith the tubular portions 2 and 4, respectively, and in the illustratedembodiment this is shown only for the plate 9 and the tubular portion 4.Such an arrangement is advantageous from a point of view of simplifyingthe production of the novel construction.

A space 11 downstream of the plate 9 in effect constitutes a collectingchamber in which the plurality of individual fluid streams are reunitedbefore passing into the passage portion 5.

As FIG. I shows a solid insert 12 is accommodated intermediate theplates 6 and 9 and has an outer diameter smaller inner diameter of thepassage portion la so that it defines with the wall of the portion 1 anannular channel 13 whose cross-sectional area according to a preferredembodiment of the invention corresponds at least substantially to thecross-sectional area of the passage portion 3.

The opposite axial end faces of the insert 12 face the plates 6 and 14so that only a portion 12a actually contacts the plate 6, whereby theapertures of the annulus 8 are free, that is they are not covered. Axialbores 16 are provided as illustrated which respectively register withapertures 18 which continuously displaces the closure member 17 to thebroken line position shown. In the illustrated embodiment the members 17are each provided with a bore 19 serving as a throttling bore andcommunicating with the hollow interior in which the spring 18 islocated. The members 17 are guided in the respective recesses 16 in asfriction-free a manner as possible so that they are slidable therein. 3

The essential point of the construction shown in FIG. 1 is that thespace in the interior of the recesses 16 and not filled by the portion17a of the member 17, is in communication with the spaces of theconstruction through which the liquid or gaseous medium flows through anaperture or opening 19 of reduced cross section, it being evident thatthe throttling bore 19 can also be replaced by grooves, channels or thelike if desired. 7

least substantially corresponds to the cross-sectional area of thepassage portion 3.

It will be appreciated that the broken line position of the member 17shown in FIG. 1 will be the normal position when no fluid flows. Whenfluid flows in the direction of the arrow 17 are displaced to theirfull-line position without exerting any throttling effect on the flowingfluid. Due to the fact that the space upstream of the members 17 throughwhich the medium flows with variable pressure, is in communication withthe interior of the recesses 16 which is not filled by the portion 17aof the respective member 17, via the throttling bore 19, obtainedbetween these two spaces so that the member 17 reciprocates to-and-froin a phase-shifted relationship. This results in a strong reduction inthe amplitudes of the exciter vibrations. Adding to this the fact thatthe medium is caused to change its direction of flow by the presence ofthe various plates, the liquid or gaseous medium passes through thepassage portion 5 almost without pulsing and therefore almost withoutcausing any further noise due to the production of vibrations.

A further embodiment is illustrated in FIG. 2. It differs from theembodiment of FIG. 1 only in the illustrated details so that theremainder of the illustration of FIG. 1 has been omitted as notessential for an understanding of the embodiment in FIG. 2. As will beseen, in FIG. 2 the members 17 have been replaced with closure membersin form of diaphragms or membranes 22 configurated as a foldablediaphragm and a plate 23 connected with the diaphragm and provided witha throttling bore or aperture 19 which communicates with the interior ofthe respective recess 16. The spring 18 again serves the same purpose asdescribed with respect to the embodiment of FIG. 1, urging the plateportion 23 into closing relationship against the apertures 8.

However, it will be appreciated that further modifications are alsopossible within the scope and intent of the present invention. It is forinstance possible to produce the insert 12 not as a separate element,but as one piece with either the annular member 31, the portion 4, orwith both. Such production can be by casting or the like. Particularlyif the medium which flows through this construction is under highpressure and if circumstances generally are disadvantageous, it ispossible to provide two or more of the arrangements in a single tubularsequence of the embodiments of FIGS. 1 and 2. Naturally, theconstruction according to the present invention need not be locateddownstream of the source of fluid, for instance a compressor, but couldbe built right into the source of fluid, that is be located within thephysical confines of the same rather than in an exteriorly locatedtubular conduit.

It has also been found that the arrangement according to the presentinvention will operate satisfactorily even if the flow of fluid is indirection opposite to that which has been illustrated in FIG. 1. It isthen only necessary to assure that the medium can act upon therespective closure members, for which puran arrangement is in form of anannular groove 24 provided in the plate 6 for the purpose of assuringthat the medium can move to the respective members 17 from the lateralregions respective apertures 8 as is the case when the flow is in normaldirection, that is the direction indicated by the arrow A.

Coming, finally, to the embodiment of FIG. 3 it will be seen that thisis somewhat analogous to, but simpler than that of FIG. 1. Theembodiment ofFIG. 3 may be used with particular advantage inapplications where only relatively small fluidflow quantities areinvolved.

Like reference numerals identify like elements as those in FIG. I. Here,however, the plates of FIG. 1 have been omitted. Instead, the element 12is provided with a single depression 16 in which the element 17 isslidably guided,

constitute therewith a unit to facilitate assembly and disassembly. Themembers 30 and 32 have apertures 31 and 33 which respectivelycommunicate with the clearance 13 and the inlet 3 or the outlet 5 (viachamber 11), as the case may be. Although each member may have severalapertures, particularly the member 32 may be provided with a singleaperthrough opening coaxial with the inlet The operational principle ofthe FIG. 3 embodiment is the same as in H68. 1 and 2, i.e., the elementor piston 17 compensates and smoothes out pressure variations in thefluid flow.

it will be understood that each of the elements described above, or twoor more together, may also find a useful applicatron in other types ofconstructions differing from the types described above.

way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal ters Patentis set forth in the appended claims.

I claim:

1. A sound damping arrangement of the character respective concentricannuli of marginally located apertures; an insert accommodated saidplates and defining wit depressions bein fluid bores 0 en at saidupstream end face; and wherein sal closure mem ers are plugs slldablyaccommodated in respective ones of said bores.

6. A sound damping arrangement as defined in claim 2, said closuremembers being resiliently deflectable diaphragms 7. A sound dampingarrangement as defined in claim 6, said diaphragms consisting at leastpredominantly of yieldably deflectable material.

8. A sound damping arrangement as defined in claim 6; further comprisingsupporting means for yieldably supporting outer margin.

1 l. A sound further comprising an annular groove connecting saidrecesses

1. A sound damping arrangement of the character described, comprising afluid-conveying tubular element having a passage, including an enlargedpassage portion through which fluid flows from an inlet to an outlet ofsaid passage; an insert in said passage portion defining with the innersurface thereof an annular clearance intermediate said inlet and saidoutlet, said insert having an end face facing said inlet; a pair ofapertured annular elements in said clearance at the upstream anddownstream ends thereof, respectively; at least one depression in saidend face and being juxtaposed with said inlet; at least one closingmember juxtaposed with said inlet and closing said depression, saidclosing member having a surface facing the incoming fluid and providedwith an aperture of reduced cross-sectional area communicating with theinterior of said depression; and biasing means yieldably biasing saidclosing member to closing position tending to close said inlet.
 2. Asound damping arrangement of the character described, comprising afluid-conveying tubular element having a passage, including an enlargedpassage portion, through which fluid flows in predetermined direction; apair of plates in said passage portion axially spaced and provided withrespective concentric annuli of marginally located apertures; an insertaccommodated in said passage portion intermediate said plates anddefining with the wall of said element an annular clearance, said inserthaving respective end faces adjacent said plates and provided withrecesses each communicating with said clearance and with one of saidapertures; a plurality of depressions in the upstream one of said endfaces each registering with one of said apertures; a plurality ofclosing members each closing one of said depressions except for areduced cross-sectional area; and biasing means yieldably biasing therespective closing members towards closing positions tending to closethe respectively associated aperture.
 3. A sound damping arrangement asdefined in claim 2, wherein said plurality of depressions equal saidplurality of apertures, and said plurality of closing members equal saidplurality of depressions.
 4. A sound damping arrangement as defined inclaim 2, said passage having a predetermined cross-sectional area; andwherein each of the combined cross-sectional areas of said apertures ofeach of said annuli, of said recesses, of said depressions and of saidannular clearance at least approximates said predeterminedcross-sectional area.
 5. A sound damping arrangement as defined in claim2, said depressions being fluid bores open at said upstream end face;and wherein said closure members are plugs slidably accommodated inrespective ones of said bores.
 6. A sound damping arrangement as definedin claim 2, said closure members being resiliently deflectablediaphragms mounted in the respective depressions and deflectable intopositions partially closing the respectively associated apertures.
 7. Asound damping arrangement as defined in claim 6, said diaphragmsconsisting at least predominantly of yieldably deflectable material. 8.A sound damping arrangement as defined in claim 6; further comprisingsupporting means for yieldably supporting said diaphragms so that thesame are yieldably deflectable.
 9. A sound damping arrangement asdefined in claim 2; and further comprising an annular memberaccommodated in said annular clearance and provided with an annulus ofadditional apertures concentric with the first-mentioned annuli.
 10. Asound damping arrangement as defined in claim 9, said annular memberhaving an outer margin, and said annulus of additional apertures beinglocated in the region of said outer margin.
 11. A sound dampingarrangement as defined in claim 2; further comprising an annular grooveconnecting said recesses in the downstream one of said plates and havingan open side facing towards said upstream plate.